Smog unit 3 and 4

1) What is the substance used in a vapor canister to absorb volatile organic compounds?

A) Desiccant

B) Organic absorber

C) Pleated paper

D) Charcoal

D) Charcoal

2) Which valve(s) is (are) normally closed?

A) Canister purge valve

B) Canister vent valve

C) Both canister purge and canister vent valve

D) Neither canister purge nor canister vent valve

A) Canister purge valve

3) All of the following can increase the pressure in the evaporative emission system EXCEPT ________.

A) fuel temperature

B) returned fuel from the fuel injection system

C) inlet fuel to the fuel pump

D) volatility of the fuel

C) inlet fuel to the fuel pump

4) Inadequate purge flow rate will trigger which DTC?

A) P0440

B) P0446

C) P0300

D) P0440 or P0446

B) P0446

5) Which EVAP valve is subject to rust and corrosion more than all of the others?

A) Purge valve

B) Vacuum control valve

C) Vent valve

D) Roll over check valve

C) Vent valve

6) A small leak is detected by the evaporative emission control system monitor that could be

caused by a loose gas cap. Which DTC will likely be set?

A) P0441

B) P0442

C) P0446

D) P0440, P0441, or P0442

B) P0442

7) Exhaust gas recirculation (EGR) is generally not needed under any of the following conditions

EXCEPT ________.

A) idle speed

B) cold engine

C) cruise speed

D) wide open throttle (WOT)

C) cruise speed

8) EGR is used to control which exhaust emission?

A) Oxides of nitrogen (NOx)

B) Unburned hydrocarbons (HC)

C) Carbon monoxide (CO)

D) Both NOx and CO

A) Oxides of nitrogen (NOx)

9) When testing an EGR system for proper operation using a vacuum gauge, how much should

intake manifold vacuum drop when the EGR valve is commanded open by a scan tool?

A) 6 to 8 in. Hg

B) 1 to 2 in. Hg

C) 3 to 5 in. Hg

D) 8 to 10 in. Hg

A) 6 to 8 in. Hg

10) A P0401 DTC (exhaust gas recirculation flow insufficient) is being discussed. Technician A says that a defective EGR valve could be the cause. Technician B says that clogged EGR passages could be the cause. Which technician is correct?

A) Technician A only

B) Technician B only

C) Both technicians A and B

D) Neither technician A nor B

C) Both technicians A and B

11) Before an evaporative emission monitor will run, the fuel level must be where?

A) At least 75% full

B) Over 25%

C) Between 15% and 85%

D) The level in the tank is not needed to run the monitor.

C) Between 15% and 85%

12) Technician A says that low pressure smoke installed in the fuel system can be used to check for leaks. Technician B says that nitrogen under low pressure can be installed in the fuel system to check for leaks. Which technician is correct?

A) Technician A only

B) Technician B only

C) Both technicians A and B

D) Neither technician A nor B

C) Both technicians A and B

13) OBD-II regulations require that the EGR system be tested. Technician A says that the PCM can monitor the commanded position of the EGR valve to determine if it is functioning correctly. Technician B says that the PCM can open the EGR valve and monitor for a change in the oxygen

sensor voltage to detect if the system is functioning correctly. Which technician is correct?

A) Technician A only

B) Technician B only

C) Both technicians A and B

D) Neither technician A nor B

C) Both technicians A and B

14) A vehicle comes into the shop and the technician retrieves the diagnostic code P0401 "EGR flow insufficient." Which of these could be the cause?

A) Clogged EGR ports or passages

B) EGR valve stuck open

C) Electrical wiring shorted

D) All of these are correct.

A) Clogged EGR ports or passages

15) On a vehicle with an ORVR system, the fuel tank is vented to the ________ during refueling.

A) atmosphere

B) charcoal canister

C) throttle body

D) air filter

B) charcoal canister

16) A leak detection pump (LDP) is used on some vehicles to ________ the fuel system to check

for leaks.

A) apply vacuum

B) heat

C) cool

D) pressurize (slightly)

D) pressurize (slightly)

17) A fuel tank expansion chamber is designed to be what percentage of the tank capacity?

A) 10-20%

B) 2-5%

C) 25-30%

D) None of these

A) 10-20%

18) What polluting chemical compound is caused by evaporating gasoline?

A) Volatile organic compounds (VOCs)

B) Carbon monoxide

C) Ozone

D) None of these

A) Volatile organic compounds (VOCs)

19) Technician A says that fuel filler caps with pressure and vacuum vents are used with EVAP system fuel tanks. Technician B says that using a non-vented cap on a system equipped with an evaporative emissions system may cause damage to the fuel tank. Which technician is correct?

A) Technician A only

B) Technician B only

C) Both technicians A and B

D) Neither technician A nor B

C) Both technicians A and B

20) Technician A says that canister purging occurs during wide open throttle conditions. Technician B says that canister purging uses intake manifold vacuum to pull fuel vapors from the canister. Which technician is correct?

A) Technician A only

B) Technician B only

C) Both technicians A and B

D) Neither technician A nor B

B) Technician B only

21) Beginning with the 2000 model year, enhanced EVAP systems were introduced that can

detect a leak as small as ________.

A) 0.020 in.

B) 0.040 in.

C) 0.002 in.

D) None of these

A) 0.020 in.

22) Many vehicle manufacturers use the ________ sensor as the EGR monitor on some

applications.

A) RPM

B) intake air temperature (IAT)

C) throttle position (TP)

D) manifold absolute pressure (MAP)

D) manifold absolute pressure (MAP)

23) Which of these components is the EVAP system purge valve?

A) A

B) B

C) C

D) D

B) B

1) The PCV system controls which exhaust emission(s)?

A) HC

B) CO

C) NOx

D) Both A and B

D) Both A and B

2) How much of the air needed by the engine flows through the PCV system when the engine is

at idle speed?

A) 1 to 3%

B) 5 to 10%

C) 10 to 20%

D) Up to 30%

D) Up to 30%

3) Technician A says that if the PCV valve were defective or clogged, the engine could idle rough. Technician B says that the engine may stall. Which technician is correct?

A) Technician A only

B) Technician B only

C) Both technicians

D) Neither technician

A) Technician A only

4) Technician A says that if a PCV valve rattles, then it is okay and does not need to be replaced. Technician B says that if a PCV valve does not rattle, it should be replaced. Which technician is correct?

A) Technician A only

B) Technician B only

C) Both technicians A and B

D) Neither technician A nor B

B) Technician B only

5) Technician A says that the PCV system should create a slight pressure in the crankcase at idle. Technician B says that the PCV system should create a slight vacuum in the crankcase at 2,500 RPM. Which technician is correct?

A) Technician A only

B) Technician B only

C) Both technicians A and B

D) Neither technician A nor B

B) Technician B only

6) The SAI system is used to reduce which exhaust emission?

A) HC

B) CO

C) NOx

D) Both HC and CO

D) Both HC and CO

7) Two technicians are discussing exhaust check valves used in SAI systems. Technician A says that they are used to prevent the output from the SAI pump from entering the intake manifold. Technician B says the check valves are used to keep the exhaust from entering the AIR pump.

Which technician is correct?

A) Technician A only

B) Technician B only

C) Both technicians A and B

D) Neither technician A nor B

B) Technician B only

8) Where is the output of the AIR pump directed when the engine is cold?

A) Exhaust manifold

B) Catalytic converter

C) Air cleaner assembly

D) To the atmosphere

A) Exhaust manifold

9) The switching valves on the AIR pump have failed several times. Technician A says that a defective exhaust check valve could be the cause. Technician B says that a leaking exhaust system at the muffler could be the cause. Which technician is correct?

A) Technician A only

B) Technician B only

C) Both technicians A and B

D) Neither technician A nor B

A) Technician A only

10) When checking for the proper operation of the AIR system using an exhaust gas analyzer, how much should the oxygen levels increase when the pump is allowed to function?

A) 1-4%

B) 5-10%

C) 10-20%

D) Up to 30%

A) 1-4%

11) Technician A says that CO and HC levels should increase if the AIR hoses are pinched off. Technician B says that a defective drive belt may cause AIR system problems. Which technician is correct?

A) Technician A only

B) Technician B only

C) Both technicians A and B

D) Neither technician A nor B

C) Both technicians A and B

12) The electric AIR pump is energized for ________.

A) no longer than 4 minutes

B) until the engine goes into closed loop

C) Either A or B

D) Neither A nor B

C) Either A or B

13) Which device protects the air pump from reverse exhaust pressure?

A) Check valve

B) PCV valve

C) EGR valve

D) IAC valve

A) Check valve

14) In what year did PCV system monitoring become mandatory?

A) 2004

B) 1996

C) 1988

D) 2000

A) 2004

15) Technician A says that a 3 × 5 card should be held against the oil fill opening if the PCV system is operating correctly. Technician B says that if a PCV valve rattles, it definitely is good. Which technician is correct?

A) Technician A only

B) Technician B only

C) Both technicians A and B

D) Neither technician A nor B

A) Technician A only

16) An electric SAI pump is controlled by ________.

A) a vacuum switch

B) the PCM

C) exhaust pressure

D) manifold vacuum

B) the PCM

17) What term is used to describe combustion gasses leaking past cylinder rings?

A) Blow by

B) Manifold pressure

C) Sludge

D) Crankcase build-up

A) Blow by

18) Technician A says that PCV valves should rattle when shaken. Technician B says that a defective PCV system may cause leaking engine seals. Which technician is correct?

A) Technician A only

B) Technician B only

C) Both technicians A and B

D) Neither technician A nor B

C) Both technicians A and B

19) A P0410 DTC indicates a problem with ________.

A) the SAI solenoid

B) MAF airflow

C) the idle control system

D) None of these

A) the SAI solenoid

20) All engines are equipped with a PCV valve.

A) True

B) False

B) False

1) A freeze frame is generated on an OBD-II vehicle ________.

A) when a type C or D diagnostic trouble code is set

B) when a type A or B diagnostic trouble code is set

C) every other trip

D) when the PCM detects a problem with the O2S

B) when a type A or B diagnostic trouble code is set

2) An ignition misfire or fuel mixture problem is an example of what type of DTC?

A) Type A

B) Type B

C) Type C

D) Type D

A) Type A

3) The comprehensive component monitor checks computer controlled devices for ________.

A) opens

B) rationality

C) functionality

D) All of the above

D) All of the above

4) A freeze-frame is a ________ of all data at the instant an emission-related DTC is set.

A) comprehensive component monitor

B) failure record

C) snapshot

D) trip

C) snapshot

5) Which of these is a continuous monitor?

A) Fuel system monitor

B) EGR monitor

C) Oxygen sensor monitor

D) Catalyst monitor

A) Fuel system monitor

6) DTC P0302 is a ________.

A) generic DTC

B) vehicle manufacturer-specific DTC

C) idle speed-related DTC

D) transmission/transaxle-related DTC

A) generic DTC

7) Enable criteria means ________.

A) the same thing as a trip

B) conditions for a particular test to be performed

C) a drive cycle

D) a warm-up cycle

B) conditions for a particular test to be performed

8) By looking at the way diagnostic trouble codes are formatted, which DTC could indicate that the gas cap is loose or defective?

A) P0221

B) P1301

C) P0442

D) P1603

C) P0442

9) The computer automatically clears a DTC if there are no additional detected faults after

________.

A) forty consecutive warm-up cycles

B) forty-five warm-up cycles

C) one consecutive trip

D) five key-on/key-off cycles

A) forty consecutive warm-up cycles

10) A global scan tool can display data under ________ modes of operation.

A) dual

B) nine

C) only three

D) fifteen

B) nine

11) OBD II has been on all passenger vehicles in the United States since ________.

A) 1986

B) 1991

C) 1996

D) 2000

C) 1996

12) A pending code is set when a fault is detected on ________.

A) a one-trip fault item

B) the first fault of a two-trip failure

C) the catalytic converter efficiency test

D) a thermostat problem (too long to closed-loop status)

B) the first fault of a two-trip failure

13) Technician A says that when the MIL is on, the technician should retrieve the DTC and follow the manufacturer's recommended procedure to find the root cause of the problem. Technician B says that all OBD II monitors must have the enable criteria achieved before a test

is performed. Which technician is correct?

A) Technician A only

B) Technician B only

C) Both technicians A and B

D) Neither technician A nor B

C) Both technicians A and B

14) The MIL is turned off under any of the following conditions, EXCEPT ________.

A) codes are cleared with a scan tool

B) power to the PCM is disconnected

C) vehicle is driven on 3 consecutive trips with a warm-up cycle, without detecting a fault

D) PCM diagnostic link is grounded

D) PCM diagnostic link is grounded

15) Technician A says that OBD-II includes generic as well as vehicle manufacturer's specific

DTCs and data displays. Technician B says that OBD-II have common DTCs. Which technician

is correct?

A) Technician A only

B) Technician B only

C) Both technicians A and B

D) Neither technician A nor B

C) Both technicians A and B

16) The ________ is a software program that is designed to manage the operation of all OBD-II

monitors by controlling the sequence of steps necessary to execute the diagnostic tests and

monitors.

A) trip manager

B) task manager

C) PCM monitor

D) sequence manager

B) task manager

17) Which one of these is NOT a continuous monitor?

A) Fuel trim monitor

B) Misfire monitor

C) Thermostat monitor

D) Comprehensive component monitor

C) Thermostat monitor

18) A U type DTC indicates a problem with ________.

A) powertrain

B) body and accessories

C) communication related systems

D) suspension system

C) communication related systems

19) An element of the OBD II diagnostic management system which stores engine data during a

DTC set is called ________.

A) misfire

B) vehicle in vehicle out

C) freeze frame

D) memory account

C) freeze frame

20) On-board diagnostic (OBD) systems I and II are being discussed. Technician A says that OBD II systems require misfire detection. Technician B says that OBD I was capable of detecting exhaust emission control system failures. Which technician is correct?

A) Technician A only

B) Technician B only

C) Both technicians A and B

D) Neither technician A nor B

A) Technician A only

21) In an OBD II system, when all enabling criteria for a given diagnostic is met, it's considered

which of these terms?

A) A freeze frame

B) A trip

C) A warmed-up engine

D) A tuned engine

B) A trip

22) Technician A says that a warm up cycle is a trip where the engine reaches at least 160 °F.

Technician B says that OBD II requires the diagnostic system to monitor all emission-related

components and systems. Which technician is correct?

A) Technician A only

B) Technician B only

C) Both technicians A and B

D) Neither technician A nor B

C) Both technicians A and B

23) Which organization developed guidelines for OBD II?

A) EPA

B) CARB

C) DOT and EPA

D) EPA and CARB

D) EPA and CARB

24) Which of these is checked during an OBD II PCM initiated functionality test?

A) ECT

B) O2 sensor

C) Transmission shift solenoids

D) Brake switch

C) Transmission shift solenoids

25) Mode six information can be used to ________.

A) check monitor status before starting repairs

B) identify the component that caused the fault

C) Both A and B

D) Neither A nor B

C) Both A and B

26) The PCM will not run certain monitors if ________.

A) the MIL is on

B) the MIL is off

C) the weather is cold

D) vehicle speed is excessive

A) the MIL is on

27) A type C DTC will light the MIL.

A) True

B) False

B) False

28) Setting a type B DTC will also trigger a freeze frame.

A) True

B) False

A) True

1) Technician A says that reprogramming an engine control module using the J2534 system requires a factory scan tool. Technician B says that reprogramming an engine control module using the J2534 system requires Internet access. Which technician is correct?

A) Technician A only

B) Technician B only

C) Both technicians A and B

D) Neither technician A nor B

B) Technician B only

2) What method can be used to reprogram an engine control module?

A) On-board

B) Off-board

C) Remote

D) Any of the above

D) Any of the above

3) A battery maintainer is used during reprogramming to ________.

A) make sure the OBD-II data is not lost

B) make sure the customer's radio stations are not lost

C) make sure the system voltage does not drop during the reprogramming event

D) All of the above

C) make sure the system voltage does not drop during the reprogramming event

4) What is NOT required to reprogram a vehicle's engine control module?

A) A good Internet connection

B) A manufacturer's scan tool

C) A pass-through device

D) A computer that meets the minimum specifications

B) A manufacturer's scan tool

5) SAE J2534 is a mandated specification to all automakers who sell vehicles in the United

States after 2004 to ________.

A) have standard data link connectors

B) support reprogramming the EEPROM

C) make service information available to all who service vehicle emissions

D) All of the above

D) All of the above

6) How was programming updated in the early 1980s?

A) A new computer had to be installed

B) A replaceable PROM was used

C) The control cable was replaced

D) The instrument panel cluster (IPC) was updated

B) A replaceable PROM was used

7) What type of battery charger is specified when reprogramming?

A) Must be a low-voltage, high amperage charger

B) Must be a battery charger that produces little, if any, voltage fluctuations

C) Must be able to communicate with the J2534 unit

D) Needs to be OBD/CARB approved

B) Must be a battery charger that produces little, if any, voltage fluctuations

8) What organization created the J2534 standard?

A) EPA

B) CARB

C) SAE

D) OBD

C) SAE

9) What does a pass-through device do?

A) It is used between the vehicle and the scan tool.

B) It passes data between the DLC and the computer used to program the vehicle.

C) It is used only for off-board programming.

D) It is used to monitor the data being transferred.

B) It passes data between the DLC and the computer used to program the vehicle.

10) Aftermarket programmers may create an issue of ________.

A) noncompliance

B) excessive cost to the vehicle owner

C) not being certified by EPA/CARB

D) Both A and C

D) Both A and C

11) Reprogramming consists of ________ from the manufacturer.

A) replacement DVDs

B) obtaining a memory stick

C) downloading new calibrations

D) a new EEPROM

C) downloading new calibrations

12) Access to programming software is obtained from ________.

A) SAE

B) NASTF

C) CARB

D) EPA

B) NASTF

13) Which one of these is a manufacture specific pass-through device?

A) GM Tech 2

B) GM MDI

C) CarDAQ-Plus

D) Drew Technologies remote

B) GM MDI

14) Some shops are hesitant to perform reprogramming because of ________.

A) concerns about process failure

B) possible damage to the vehicle module

C) lack of computer skills

D) All of these

D) All of these

15) What type of programming does NOT require that the vehicle be taken to the dealer?

A) Pass-through programming

B) PROM replacement

C) OTA updates

D) None of these

C) OTA updates

16) A feature of SAE standard J2534 version 5.0 is ________.

A) improved communications

B) a smaller J1962 connector

C) an 18-pin connector

D) All of these

A) improved communications

17) Which of these would be a concern when using installing an aftermarket "tuner" in a vehicle?

A) Engine damage

B) Emission test failure

C) Both A and B

D) Neither A nor B

C) Both A and B

18) Which type of programming relies on a third party to have the manufacturer software

subscription?

A) Off-board programming

B) Over-the-air programming

C) Remote programming

D) In-shop programming

C) Remote programming

19) In 1996 as part of the OBDII requirements, all modules that were responsible for emissions

control were required to have ________.

A) sealed PROM covers

B) a removable PROM

C) only one connector

D) EEPROMs

D) EEPROMs

20) The purchase and programming of a module at a local parts store is an example of ________

programming.

A) on-board

B) off-board

C) remote

D) over-the-air

B) off-board

1) Technician A says that the first step in the diagnostic process is to verify the problem (concern). Technician B says that the second step is to perform a thorough visual inspection. Which technician is correct?

A) Technician A only

B) Technician B only

C) Both technicians A and B

D) Neither technician A nor B

C) Both technicians A and B

2) Which item is NOT important to know before starting the diagnosis of an engine performance

problem?

A) List of previous repairs

B) Brand of engine oil used

C) Type of gasoline used

D) The temperature of the engine when the problem occurs

B) Brand of engine oil used

3) After completing repairs the technician should perform a ________ to allow the PCM to

conduct monitor tests.

A) battery disconnect

B) DTC survey

C) drive cycle

D) fuel milage test

C) drive cycle

4) Which step should be performed LAST when diagnosing an engine performance problem?

A) Checking for any stored diagnostic trouble codes

B) Checking for any technical bulletins

C) Performing a thorough visual inspection

D) Verifying the repair

D) Verifying the repair

5) Technician A says that if the opposite DTC can be set, the problem is the component itself. Technician B says that if the opposite DTC cannot be set, the problem is with the wiring or grounds. Which technician is correct?

A) Technician A only

B) Technician B only

C) Both technicians A and B

D) Neither technician A nor B

C) Both technicians A and B

6) The preferred method to clear diagnostic trouble codes (DTCs) is to ________.

A) disconnect the negative battery cable for 10 seconds

B) use a scan tool

C) remove the computer (PCM) Power feed fuse

D) cycle the ignition key on and off 40 times

B) use a scan tool

7) What is the factory scan tool for Chrysler brand vehicles equipped with CAN?

A) wiTECH

B) Tech 2

C) NGS

D) Master Tech

A) wiTECH

8) Which of these is NOT part of a visual inspection?

A) Check oil level

B) Check coolant condition

C) Check battery voltage

D) Check DTCs

D) Check DTCs

9) Technician A says that knowing if there are any stored diagnostic trouble codes (DTCs) may be helpful when checking for related technical service bulletins (TSBs). Technician B says that only a factory scan tool should be used to retrieve DTCs. Which technician is correct?

A) Technician A only

B) Technician B only

C) Both technicians A and B

D) Neither technician A nor B

A) Technician A only